1. Field of the invention
The invention relates to a bombardment-inhibiting bulletproof glass pane or automobiles, composed of a plurality of silicate glass panes with intermediate layers of thermoplastics polymer disposed between them. On the interior surface of the bulletproof glass pane, a sheet or plate of impact-resistant plastics material is mounted by means of a thermoplastics adhesive film such that, in the installed state, this sheet faces towards the passenger compartment. On the exterior surface of the bulletproof glass pane is a scratch-resistant coating.
2. Description of the Related Art
Bombardment-inhibiting bulletproof glass panes are conventionally known. For example, DE 34 21 571 describes a bulletproof glass pane consisting of three silicate glass sheets each 6 mm thick, which are connected together by 0.76 mm thick polyvinyl butyral sheets. On the surface towards the passenger compartment, a plate of polycarbonate is bonded by a thermoplastics polyurethane layer to the bulletproof glass pane. On the exterior surface, the bulletproof glass pane is provided with a soft elastic polyurethane film having a self-healing characteristic.
Providing a plate of impact-resistant plastics, such as polycarbonate, on the rear face of the bulletproof glass pane, reliably prevents splinters from flying on this face in case of bombardment. On the other hand, with glazing of this type, problems arise with exposure to solar radiation due to the different thermal expansions of the rear polycarbonate plate and the silicate glass sheet. The shear stresses that arise in the adhesive film between the polycarbonate plate and the glass surface can, at high temperature, lead to deformations or even to breaking-away of the polycarbonate plate. It is therefore desirable to provide a bulletproof glass pane in which the risk of a deformation or breaking away of the polycarbonate plate due to exposure to solar radiation is prevented or at least greatly reduced.